The AC-DC chip is an integrated circuit used to convert alternating current (AC) into direct current (DC), and is widely applied in power adapters, chargers, industrial power supplies, and other scenarios. According to its topological structure and working principle, AC-DC chips can be classified into the following categories:
PFC (Power Factor Correction) chip
- Used to enhance the power factor (PF) of the power supply, reduce harmonic interference. Usually, it adopts the Boost boost topology, which can be divided into active (Active PFC) and passive (Passive PFC) types.
High-frequency QR (Quasi-resonant) Chip
- Reduces switching losses through Valley Switching technology, enhancing efficiency. It is commonly used in Flyback topologies and is suitable for medium and low-power applications.
LLC Resonant Chip
- Utilizes LLC resonant topology (inductor-inductor-capacitor), achieving high efficiency through soft-switching technology, suitable for high-power applications (such as server power supplies, TV power supplies, etc.).
PFC + LLC Combo Chip
- A combined chip integrating PFC and LLC control functions, offering high power factor and high efficiency, and commonly used in high-power power supply designs.
Forward topology chip
- Transmits energy directly through a transformer, suitable for medium to high power scenarios. It requires the use of synchronous rectification or flyback diodes.
Flyback Chips
- SSR Flyback (Secondary Side Control): Controls the output voltage through feedback on the secondary side, with high accuracy.
- PSR Flyback (Primary Side Control): Detects the output voltage on the primary side, eliminating the need for optocouplers and simplifying the design, suitable for low-cost solutions.
Synchronous Rectification (SR) Chip
- Replaces diode rectification with MOSFETs to reduce conduction losses and improve efficiency. It is often used in conjunction with topologies such as flyback and LLC.
Summary:
The AC-DC chip is an integrated circuit that converts an alternating current input into a stable direct current output through a specific topology and control technology. Its design must take into account efficiency, power factor, cost, and reliability, and be suitable for the application requirements of different power levels.
